Hydraulic valve mechanism



Fb. 16, 1943. H. z. GoRA 2,311,336

l HYDRAULIC VALVE MECHANISM Fil'ed July 27, 1940 5 Sheets-Sheet l Feb. 16, 1943.

H. z. GQRA HYDRAULIC VALVE MEGHANISM Filed July 27, 1940 5 sheets-sheet 2 amm/@Mdm Feb. 16, 1943. H. z, GORA HYDRAULIC VALVE MECHANISM Filed July 27, 1940 5 Sheets-snee?l 5 Feb.16,1943. "H1, @ORA 2,311,336 I I 'HYDRAULIC lVALVE MECHANISM Filed July 27, 1940 5 Sheets-Sheet 4 (All Y \li1 1\ 112 e9 94 zo@ Feb. 16, '1943. I H. zQGoRA 2,311,336

1 4mmRAUmc VALVE MECHANISM Patented Feb. 16, i943 UNITE,

A HYDRAULIC :VALVE MECHANXSM V.Iiienry Z. Gora, Bridgeport, Conn., assignor to l .Jenkins `Bros.,lNew York, N. Y., a -corporation offNew Jersey Applicationiu'ly 11940, Serial No. 348,051

desirable that the press be-opened and closed by use` of what will be referred to asY low` pressure uid, whereas theactual molding of the stem should be eifected under what Will'be referred to ashigh pressure'fiuid in order that the stem material may 'be fforced into every part ofthe mold `by a .iinalvexertion of high pressure and then retained Vunder this pressure during the period when the stem material is being cured-as by vulcanization.

It isan object .of this invention Vtoprovide-an improved Valve mechanism for controlling the flow of motive luidito a:.press ytoleffectuate the foregoing cycle of operation.

It `has heretofore Vbeen proposed .l to f provide a hydraulic press withsequentially operated-.valves for admitting. irst low pressure 'iiuid andthen high pressure `fluid to" the press with `provisions forlocking the actuator for the high pressure and rexhaust' valves against movement `until the low pressure valve has been operated to establish the designed low pressure-in the press, the proposed construction employinga lever for 'operating thelow pressure valvefpivoted on azrotata-ble 'cam `for operating. thechigh lpressure and exhaust valves when lateral rotation is applied to the lever andthereby to the cam, said `cam having a pressure operated. means for .locking the same` against :rotationuntilthe lever operated valve has "been openedto admit .the low pressure to thepress, following kzwhiclfi said cam is released by'V said lockingfmeans. and: the' lever may be rotated laterally out of operative relationshipito .thelowipressure valve,..:to .-permitthe sameztotfclosegwhereupon the high pressure and exhaust yalVesareLoperabIe frornth'e cam. JA.

devicerof the 4typefjust referred to, however, Ais open* to. various .objections among which may; .be notedthe'. need for. the. operator to align thelever with -thelovv pressure v4valve for v`operating the.latteigthe` need forV imparting l'different kinds and directionsof .movementzto the-same operating element in .proper .sequence .an-dat vproper intervals, the. need 'for lplural locks or.: stops@ When the operating member ymayrnovein .a plurality of directions, the .strain on .and .eventual .looseness atthe pivotfof 'thelflever :arising :fromfthe use of .the'lever :as .an actuator fforitherotary cam, the Hlackpf assurance the valves will1be operated in the desired sequenCe,:.etc.

- It is .an object `oi .this :invention .to .provide 1 a device. ofthe typefcharacterized .whichxis of irnprovedv and simplified construction and. operation so that itv involves only one kindxof. movementy on the part of athe. operator, Yrequiresno close observation; in `.order` that ;the proper operating `positions shall be :reachedi and ,maintained, assures operation ina desiredsequence,y etc.

It has also been proposed to :provide apinrality of hydraulic presses :with pairs of `,inlet and outlet valves :f or controlling ,the resptive presses, and toernployiaf'rotary or r-ectilinearly movable actuator provided :withicam projections for operating all of. said :valves `to vthefendthat the inlet.. and gout-letrval-Ves ,of one, pressl may be respectively in open: and closed;positiomvvhilev the inlet and outlet -valves.:,ofa..sec.ond.presseare respectively in closedcangd f open pos'itonsizso that the pressure fluid may be admitted to and exhausted froinl thetWoVv `presses in alternation. ,IA

structure of this type, however, Ybecausoof :the

very sequence of valve operation entailed thereby, renders such.- av construction'` inapplicable ato; the eicient control ofi sequentially.,,applied 'low )and high pressures tota`A- single. press. cylinder. A

It is.an object of this. invention to 4,provide an improved. valve mechanism ofitheutypeutilizingY a rotatable disk `provided y,'vitlrcani ,projections which is suitable for eiiciently. ,controlling in. succession-:the admissionr to `.and .release `from a single cylinderfofloxvvand high .pressurefluid It has also been ..proposed..to; .provide at-,hydraulicpressl with .a;,low-pressure;admission valve, a highgpressure admission yalve, .and,.an;exhaust valve iwhich .xmaylbe {operated- 1. in i sequence :,by, a

single cam actuator. lnasmuehas.aconstruction of; this character i involves ,the Yiihaus tinggof-g the high pressure t0 Was-te; there-1s ainarkedxless; :in

efficiency.

It is1an obj-ect of this invention-:togprovida an improved Lvalve mechanism ywhereby :.the i high pressureffiluid, .,whenreleased. exhausts: into. the source of 'zlovv .pressure,. Soas v.to `conservethe energy involved in placing thefiuid underpressure.

'Another object. of Vthis .invention 'is to.4 provide an improved valve mechanism of the type just characterized which is applicable to a press wherein a period of low pressure in the press follows the application of high pressure.

Another object of this invention is to provide an improved valve mechanism of the type hereinbefore referred to which employs a pilot valve in conjunction with one or both of the valves operated to release-or reduce the pressure where-V by the operating mechanism is relieved of the strain incident to opening a main exhaust or relief valve against the pressure then existing in the press.

Another object of this invention is to provide a device of the type last characterized wherein each pilot valve and its associated exhaust or relief valve are operated in proper sequence by a single operating means.

Another object of this invention is to provide an improved valve mechanism for controlling the flow of low and high pressure iluid and which includes improved means for predetermining when, after operation of the low pressure valve, the high pressure valve may be operated.

Another object of this invention is to provide an improved valve mechanism of the type hereinbefore characterized which is so constructed that the stations of the valve actuator are easily determined by the operator so as to simplify the operation, relieve the operator of close observation, assure a designed cycle of operation, and minimize the chances of improper operation through carelessness or lack of attention.

Another object of this invention is to provide an improved valve mechanism of the type hereinbefore characterized which is simple in construction, strong, durable and ecient.

Other objects will appear as the description of the invention proceeds.

The invention is capable of receiving a variety of mechanical expressions only one of which is illustrated on the accompanying drawings, and it is to be expressly understood that the drawings are for purposes of illustration only and are not to be construed as a definition of the limits of the invention, reference being had to the appended claims for that purpose.

Referring in detail to the accompanying drawings, wherein the same reference characters are employed to designate corresponding parts in the several figures,

Fig. 1 is a vertical cross section, schematic in character, showing an embodiment of the present invention with the several valves and their operative means projected into a single plane for the sake of clearness of understanding, instead of being clustered around the axis of the rotatable valve actuator;

Fig. 2 is an elevation, partly in section, of the embodiment of Fig. 1 to illustrate the locking means and its operating means ;1

Fig. 3 is a plan view of said embodiment to illustrate the grouping of the several valves and the'extreme positions of the valve actuator; and

' Figs. 4 to 8 inclusive are diagrammatic views to illustrate successive positions of the valve mechanism of'this embodiment in the. course of a complete cycle of operation.

It is to be understood that the present invention may be used for controlling the flow of highV scribed is associated With'ahydraulic pressof any suitable construction, such for example as appropriate for use in the molding and curing of rubber valve stems for pneumatic tires, wherein the cylinder of the press is to be supplied first with loW pressure fluid to move the movable press head into its closed position, then with high pressure fluid in the same cylinder to effect the iinal bump necessary to force the movable press head home in order to assure that the molded material is forced under high pressure'into every part of the mold, where in the case of rubber valve stems the high pressure will be held during Athe curing or vulcanization of the stem, after which the high pressure is released and there is a period of low pressure in the cylinder of the press during the withdrawal of the movable press head from its pressing position to its open position where, for example, a new set of molds may be introduced into the press.

With this understanding the cylinder of the press is connected through any suitable conduits or piping with the connection I0 (Fig. 2) of a valve housing I2, said connection I0 leading through opening I3 into chamber I4 suitably formed in the housing I2. Suitably formed in the wall of the chamber I4,'as on a threaded sleeve I5, is a valve seat I6 designed to be engaged by a valve member I'I. Valve member I'I is normally urged by a spring toward closed position, and in the preferred embodiment of the invention has associated therewith a pilot valve, preferably mounted to control a port through the main valve member II. Any suitable construction to carry into effect the foregoing purposes may bel employed. As shown, valve member I'I has a hollow sleeve-like extension I8 projecting from the rear face thereof and slidably mounted in a recess I I formed in the housing I2 or the cover plate 3I thereof, and extending through the valve member proper is a passage I9, here shown as suitably formed to receive a threaded sleeve providing a valve seat 2|. Mounted in the hollow bore 22 of the sleeve I8 is a pilot valve member 23 movable freely in said bore and guided thereby, said bore 22 being in communication with the chamber I4 through a suitable passage or passages I56. From the forward face of said pilot valve member 23 projects a pin 24 which is guided in an apertured bridge 25 across the open end of the passage I9, said pin 24 being of such length that when the valve member 23 is engaged with the seat 2I said pin 24 projects beyond the face of the valve member I1 for a purpose hereinafter explained. Co-operating with the rear faceof the pilot valve member 23 is a coil spring 26 which reacts between the same and a seat 27,

here shown as formed in a threaded plug 28 provided with a projection 29 for engagement by a wrench, so that the tension of the spring may be adjusted by threading the plug 28 into or out of its opening 30 formed in the housing I2 or the separate cover plate 3| thereof. The port 32 from the valve seat I6 leads to an exhaust opening 33 communicating with any suitable connection 34 (Fig. 3) which may lead .to Waste or to return piping for the pumping or compressor system that develops hydraulic pressure.

Communicating with the chamber I4 is a passage 35 for the admission of high-pressure uid, said passage 35 communicating through a suitable port 36 with the chamber 3'I Vof the high.

pressure admission valve, said chamber in turn connecting through passage'38 with any suitable connection39 (Fig. 3)*1eading from the source of high pressure.

Surrounding the port 36 Vis valve seat 66 provided in any suitable way in the wall ofthe chamber 31 and here shown'as formed Yon a threaded sleeve 4I. A with said seat 43 is high pressure admission valve member 42, here shown as 'guided in an apertured sleeve 43 which may be formed asan extension on the sleeve 4 I. Coeoperating with valve member t2 is a coil spring i!! which reacts between said valve member and a seat in a plug 45 threaded into a suitable aperture in the housing I2 and having an exterior extension 46 where it may be engaged by a wrench for operating said plug to` adjust the tension of the spring 44 by threading said plug into or out of its aperture in the housing.

Communicating with theopenii'ig I3 leading to the press is the chamber 48 of a valve for controlling the low of high pressure uid from the cylinder of the press to the source of low. pressure fluid.v Suitably formed in the wall of the chamber 4S and here shown as formed on a threaded sleeve 9 is a valve seat 50 with which co-operates a valve member I. Valve member 5I also preferably has associated therewith ra pilot valve, and as here shown the construction of valve member 5i with its associated pilot valve member is the same as that above described as employed with valve member I1 and its associated pilot valve. As illustrated valve memberl has a hollow rearwardly extending sleeve-like eX- tension 52 slidably mounted in a recess 59' whose interior communicates with a passage 53 through the valve member which in turn communicates through the hollow bore of extension V52 with one or more passages I55 leading to the chamber 4S. Threadedly received in said passage 53 is a sleeve 54 provided with the valve seat 55, and co-operating with said seat 55`is a pilot valve member 5S having a pin 51 projecting from its forward face through bridge 58. Co-operating with the rear face of the valve member 55 is a'coil spring 59 which seats in a threaded plug 60 having a projection 6I for engagement by a wrench so that the tension of said spring 59 may be adjusted as heretofore explained. v

The' port 62 leading from the valve member 5I communicates with a Vsuitable chamber or passage 63 formed in the housing and which is in communication with the port 64 of a valve member for controlling the admission of ylow pressure uid. As here shown port 64 is formed'in a threaded sleeve 65 which provides a valve seat 55. {3o-operating with said seat 66 is a valve member 61 having a rearwardly extending'hollow sleeve-like extension 63 slidably mountedl in a recess 16 and in which is seated a coil spring E9, that, at its opposite end, is engaged in the seat of a threaded plug provided with an extension 1I for engagement by a wrench to eiect the adjustment of the spring 39 in a manner heretoiore made clear. The chamber 12 of said last named valve communicates through passage 13 with any suitable connection 14 (see Fig. 3) which may lead to a suitable accumulator or reservoir for the low pressure fluid.

It will be noted that the pressure of the uid in chambers It and 48, which are in communication with the press cylinder through opening I3, tends to hold valve members I1 and 5I in closed position, as well as the pilot valves associated therewith, while the pressure in chamber 10 and passage i3 tends to hold valve member 61 on' its seat.

iEach of the ioregoing valvemeans is operated by'a cam actuated plunger. High pressure valve- Co-operating s member 42 is designedtofbe Vengaged and opened by the 'end lportion 15`offa'rod 16 rectilinearly movable an ljjoperiirig ,'13 and connected yto 'a plunger` 11. yrod 13 `being shown as grooved throughout` the l aswto provide Y'against leakage 'of high pressure liquid through opening 18 Afrom the passage V:i5 through vwhich'theextremity 15 oi rod 16 pro-l jects. Y A(Dper'mn'g 18 communicates with a chamber 'I3 whichjreceives Va sleevelile member 83 in whichthe'plunger j1I lis guided. Plonger 11 atits lower` 'extremity provided vwith a` vcam follower, here A* shown :as lin -the form or"V a roller `8I the bearings Elliot which have'attened sides fior guided movement in slots 83 provided rthe lower 'extremityoi the member j130. Member :Ell may be lreta-ined against displacement in any suitable way as by a lock screw 84.

Valve member 4I1 is operated by a rod 85 con- 'nect'ed toa plunger 86 which "may slide Vin a slev'egllike'member 81, comparable to member Smsuitably lretained inthe opening'S, plunger 85 atit-s lower extremity carrying a cam follower or roller'89 whichlmay be of the same constructionand similarly guided as heretofore described in connection 'with the plunger 11 and its associatedparts. v1to`d85'is 'adapted to engage'the pin 24 on the vpilot valve member k23to lift the latter n,with respect to itsV seat, and then rodV 85 will engage the under face of the valve member I1 or its bridge 25 and lift the valve member I1, as will appearmore fully from the description of operation hereinafter contained.

Valve member' 5Il is operated by a rod/9| projectin'g' through anope'ning S2 in the housing and oonnectedto a plunger 93,'rod 8l being grooved for aproportion of its length as shown to prevent leakage of the low pressure fluid through the opening 92 in which said rod 9| is slidably mounted. Plunger 93 is connected to a cam'follower or roller Si and is slidable in a sleeve-like member '95 suitably retained in the housing I2, said vsleeve-like` member being slotted at 96 to guide the rollervd analogously as above clescribed in Vconnection with member 83 and its associated parts. Rod 9i is ldesigned to engage thel pin51' onfpilot'valve member 56 to first operate'fsai'd pilot valve member, after which said rodfSlIwill engage the under face of the valve member' 5I rits bridge 58 and open the valve member L5I analogously asY just described in conjunotionwwiththevalveiniember i1 and its as sociated pilot valve. Y

VValve member51 isf operated by rod '53 rectilinearl'y movable in Athe `opening 95 suitably formed in the housingv I2,`rod 98 being grooved for a portion of its-length to prevent leakage as heretofore explained. Rod' S8 is connected toa plunger I5@ slidable in a sleeve-like member IOI suitably'retainedinposition as by a'lock screw m2, plunger |50 having a cam follower or roller IGS which is" guided in the slots Iii@ of said sleevelike memberil, analogouslyv as with sleeve andr its associated parts.

While vfor rconvenience V'of understanding the .four valvesV so, far described are illustrated in Fig. l las rdeveloped into afsingleplane, these valves in fact'are closelyclustered as shown in Fig. 3, the correspondinglvalves in the two gures being identified by corresponding reference characters A, B,C and D. n Said valves are operated in proper sequence, as hereinafterY explained, by aY common valve actuator in the form of a disk lillsuitably mounted; as by Vball bearings |01, in

the lower; part ofthe-housing I2 or as shown n Y *greater -portio'nof n its length so n aplate |68 attached to the lower part ofthe housing I2 as by bolts or screws I 09. Plate |06, which may be of generally circular form, is mounted on a shaft and suitably guided in a bearing I I in the housing I2. `On its upper face plate |06`has suitable cam projections II2, II3, ||4 and ||5 at such distances from the axis of rotation of the plate |06 that they engage and elevate the cam followers 8|, 89,-94 and |03 to which reference has heretofore been made. Suitably attached to the shaft ||0 below the bearing II6, as by sleeve I I8 pinned thereto at IIS, is a handle member provided with a suitable Ahand grasp |2| for rotating said plate |06 around its axis between two limit stops |22 and |23. The position of said member |20 at its two extreme positions is shown by full and dotted .lines in Fig. 3.

Means are preferably provided to prevent the valve actuator from being moved to its position for operating the high pressure admission valve A until after low pressure has been admitted to the cylinder of the press and the movable press head has been closed. To this end an automatic stop is interposed in the path of movement of the handle member |20 to prevent the latter being moved into that position corresponding to the operation of the high pressure admission valve A until pressure backing up in a pressure operated device, after the movable press head has moved to its limit position, is operated to Withdraw said stop.

Referring more particularly to Fig. 2, a cylinder is formed in or suitably attached to the wall of the housing I2 as by plate |26. Cylinder |25 communicates through a suitable passage I 2'l formed in the closure plug |28 at the end 0f said cylinder, and through a suitable coupling |20, with a conduit |30 that is connected in any suitable way, as by connection |3| (Fig. 1), to the passage 35. Mounted for reciprocation in the cylinder |25 is a piston |32, shown as provided with a suitable cup leather |33, designed to move downwardly within the upper enlarged portion |34 of said cylinder |25 until it is stopped by the shoulder |35. Projecting downwardly from the piston |32 is a rod |36 which extends through and is guided by an opening |31 in the end wall of the cylinder |25. Interposed between the end of the cylinder and said piston |32 is a coil spring y |38 that normally urges the piston |32 to its uppermost position where it may be stopped by a projection |39 on the inner face ofthe plug |28. Piston |32 may be provided with an adjustable extension |40 to predetermine its position when said projection |40 engages the projection |39.

Pivotally mounted on the housing I2 or the plate |26 as at |42 is a locking lever |43 having its end |44 aligned with and engaged by the projecting end of the rod |36. The opposite or head end of said lever |43 has a downwardly projecting nose that provides a locking surface |46 and an inclined surface |41 by which the lever may be eammed out of the way when the handle member |20 is moving in a counterclockwise direction. Thus lever |43 constitutes a stop for movement to the handle member |20 in only one direction. Lever |43 is normally retained with its end |44 in engagement with the rod |36 by a plunger |48 which is mounted to reciprocate in a recess |49 and which is urged by a coil spring |50 into contact with the lever |43.

When the press is fully opened the valves are in the relative positions shown in Fig. 8.and the handle 'member-|20 is at' its eXtreme righthand position, as shown `in the drawings, in engagement with the stop |22. Valves A, C and D are fully closed because the cam followers 8|, 94 and .|03 are i-n engagementvwith the at portion of the surface of the cam actuator |06, but valve B is in wide open position because its valve member is'held in its vupper position by the rod, since the cam follower 86 is at the highest point of the cam projection IIS. Consequently, vthe opening |3 which is in communication with the press cylinder is in communication'through the chamber I4 with the port 32 and the, opening 33 leading to the exhaust. In this position of the valve the pressure uid in the press cylinder may drain out through the exhaust .and the movable press head assume its inactive or open position. Cylinder |25 is also in communication with the chamber I4 through passageV 35, and spring |33 is holding the rod |36 in its uppermost position as viewed in Fig. 2 so that the head o-f lever |43 is depressed by spring |50 and the locking surface |46 is in the l path of movement of the' handle member |20.

Assuming now that the press is to be operated, and following through a complete cycle of operationofithe valve mechanism heretofore described, the handle member |20is first moved from its extreme right-hand position as viewed in Fig. 3, and in a clockwise direction, to the position indicated by dotted lines |52 in Fig. 3, in which position said handle member |20 is engaged with and stopped by the locking face |46 of the lever |43. The positions of the parts are now as shown in Fig. 4. Valve A remains closed, and valve B is also closed because the cam follower 89 has moved to its lower position on the `ilat surface of the actuator |06 by the withdrawal of the cam projection ||3 due to the rotation ofthe ractuator |06. But this same rotation has brought cam projectionsV I I4 and I I5 into engagement with the cam followers 94 and |03 respectively, elevating the rods 9| and 98, whereby said rods respectively engage the valve members 5| and 67 to fully open valves C and D. Low pressure fiuid thus enters the chamber 'l2 through the'passage 73, and flowing through the valve port 64 of the now open valve D, andthrough the passage 63, and through the valve port 62 of the `now open valve C, said low pressure Huid enters the chamber I4 and flows to the press through the opening I3. This low pressure iluid, entering the cylinder of the press, will lmove the movable press head to its closedY position.

When the movable press head has thus been moved to its limit lposition the pressure fluid may back up throughthe passages 35 and |30 into the cylinder |25, moving the piston 32 from the position shown in Fig. 4 to the position shown in Fig; 5, against the tension of the spring |38, toelevatethe head of lever |43 and withdraw its locking face |46 from the path of movement. ofhandle member |20. Handle member |20 may vtherefore be moved from its dotted position |52 to its dotted position |53 at the extreme left-hand position ,of its movement as viewed in the drawings where said handle member engages the stopV |23. This movement of the handle member effects a corresponding rotation of the actuator |06 whereby the cam elevations .|I4 and II 5 are withdrawn from the cam followers 94 and |03 respectively to effect the closure of the valves C and D. Valve B also remains closed, but the cam elevation |I2 engagescam followertlr and through rod 'I6 the cupies all portions ofth'efmld' cavitie'smunder high pressure. `I1 the molding oflfubber valve stems, hereinbefore referred to', this'position willbe maintained while the "rubber Acrrdoi` vulcanized.

To eiect the opening of thel press, handle member 20 is Vmoved* an anticlobkwise position from its position |53 in Fig. 3`. `'l'wJotationl of thel actuator ma withdraws com projectteam from under cam'follow'er v8| whereby high pres'- sure admission valve A'isblosed. Valve VZBalso remains closed. lBut canprojections'il. and I|5 respectively begin tfoperatecaf'follwers 94 and |03.` The'rst actien'ofeam'follwe y@Il is to elevate rod 9| and 'engage the'pin'5'l of pilot valve'member 56,'v'elev'a'ting the latter to open said pilot valve.V "yfh'high'lpre'ssre in chamber le Vis thus relieved, tlfeflr'iid4 flowing through the passage orfpas'sagee |55 intd'the hollow interior of the rearwardly projectiirgr extension 52 on the valvemerriberI 5| Yand thence through the pil'otvalvr'e port/into the passage |53. Simultaneously cam 'follower' |03. has engaged the incline onv'the'can'i'projeotion |15` whereby rod 9 3 is elevated to crack the valve 'member 61,

all as shown in Fig. `6.` 'Hence the high'pressure fluid may now from the passage 63 through'passage 'i3 to, the 'reservoir' f o-rlowpressure huid. Thus the pressure which has been" generatedfin the high pressure fluid uis partlyeonsfervedat'the level of the pressure existingJ the low pressure reservoir. A

Further rotation of the actuator |06 in an anticlockwise direction causes cam. projection ,H4 to fully elevate the cam follower 94 whereby the rod 9| picls up the'valve member 5| and fully opens valve C, cam projection H5 simultaneously elevating ycam lfollower |03 Whereby through rod Q the valve member 61 is`fully elevated, and thereby valve D is fullyv opened. The parts are now in the relative positions shown in Fig. 7 and the high pressure may exhaust fully from the cylinder of the press into the reservoir for low pressure fluid. Further rotafonef-` the actuator |06 in an anticl'oclgwise direction withdraws thecamepro'jections M and H5 from the @am f qllfjwers 94 and 10?, whereby valves C and D areclosed to retain the pressure m the' 19W Pressure' reservoir, after which cam projection |3 elevates cam follower SS and rod B5 to first engage pin 24 and open pilot valve member 23, whereby the low pressure back of the valve member is released, the n uid'flowing through the passage or passages |55V from the chamber I4 through the hollow bore 22 of the sleeve-like extension on the valve member l1 and thence through the port 32 to the exhaust opening 33. Continued elevation of the cam follower 809 by the cam proj ection H3, as the handle member |-A240 approaches its extreme position' ir`i"anticloekwise direction to engage the stop |22, causes rod 85 to eventually pick up valve member and move it to its Wide open position as shown in Fig. 8, whereby the fluid in the cylinder of the press may exhaust freely through the opening |3, port 32 and opening 33, permitting the movable press head to move to its Wide open position.

` As long as pressure remains in the cylinder of the'press, the locking lever |f43jis held in its elevated position, but as the'pressure is relieved in the cylinder of the press the fluid in the cylinder |may exhaust through the passages |30 and to chamber 14, permitting spring |38 to elevate rod |35 and thereby permit spring to return the lever |43 to its original position.v '1f this foc'curs before the"liandle"m'em ber |20. has passed the stem, handle 'member |20 may cam the head ofV lever 1.423,' ouo' "the way by reason of theinclined surface L41. "I'hus the parts are' restored Vto their 'original position shown in Fig. wherein the pressf'i'sready for anew'cy'cle of operations'. i

' It"v`vill thereore'be'perceived that by the present invention a valvev mechanismhas been provided'whe'r'eby a single rotary member'moving between stops will in'proper sequentie-admit lwpressure fluid to the cylindenofthe press, andI then when'thismlowA pressure has been established in 'the press as a resultf ofthemovenient' of the movable press headtdlnitposition, said'actuatormay be moved to 4ad''n i'itthe high pressure fluid, after which' the'high pressure flui'dmay bereleased, alarge part v'ofthe energy therein being conserved" yf causing the same to flowA to the low prepre soinjce,v and thereafter the pressure'ih theI cylinder is fully released to permi'tlthe movablepress"head'to moveto openpos'ition'. Furthermore, llocking .means lhave been provided' whereby' tht-actuator may not moveto the position admitting `high' pressure fluid to" kthe cylinder until'the'press 'head'has" moved to its lint position, and this iS ffetd bythe literposition ofan automaticallyl operated 'stop'that piedeterniines thefposition" of v' tlr "actuator" during' that pdwh'fthe press' he'dwflrlloving from operi 1 ',o`r'zlose`d fposition,` but which constitetes a `lstop" 'for movement "or theatftuatr` in ohlyone dectionf" i "Thevalve'aetator of the present invention need .not vvbe clcselil'll observed, but,` alljoperations tleeof' 'are bi1' 'a Simple 316i/ement 'a .single direction', from "one limit'jpsition to another,

as determined "bretons which are so related i0" the @am prieetorls" the actuator that a mere movement to each ii'the lim'itpositionsl as determined the 'stops .assurs the" meer movements and desiredsequence Aof operation of the' valve memberst 4'obtain the 'proper effects. Furthermore, 'both' Vof the"valve'memb`ers that are opened to relieve pressure acting''n' 'the rear faces thereof and thereby tending'vt'o' `h'oldthe saine' in closed rposition 'have associated Awith them pilot operated'valvesfor'initiating the 'release' of pressure wliereby'the'diie'rence'in pressure at thetw'ofaces v'thereof'is' rs't reduced toV facilitate the opening 'ofthe' main v'a'lve members "with'a consequent reduction' in strain Aand t wear on' the' valvebperating'members'. `These pilot valves alsov posses's'anvadditiohal advantege that they minimize flow'shock; as in'elosingfeachrnain valve"en`gage`s its seat before the ass'oeiat'e'd 'pilot 'valve starts Vto "close, Athereby decreasing the'l flow but'not discontinuing the now until the pilot valve "memberengages its seat. The pilot 'valve Aasso'ci'atedwithvalve C has a further advantage'inreducing'flow 'shock in that the openingof-thi's -pilot'valve"ahead'of the main "valve initiates flovffromthe clfiarnberl, which is then under high pressure, into the passage 53 leading to the low pressure source, before the full pressure in chamber i4 .is applied through. the port 5,0,to the 'passages leading to the lowpressure source-thus eliminating the shock in the passages leading to the low pressure source which would otherwise'be caused if the full pressure in chamber |13 were applied at once to initiate the flow of this column of Huid. j

',The present invention assures economic operation by conserving the energy latent in the high pressure uid by causing it to exhaust to thelow pressure source, .and thus the presentY valve mechanism assures economical operation. The structure of the valve mechanism avoids undue complexities in` providing for the sequential operation of admission and exhaust valves for both low and high pressure fluid flowing to a single cylinder, while the character of operations Vinvolved are such that close observation or care on the part of the operator is unnecessary, whereby the chances of irregularities of operation `are minimized because of the simple and direct character o the movements involved.

The structure is not only simple in its formation and operation, but it is strong and durable in character, and thus particularlyadapted to employment in the control of` hydraulic presses by ordinary workmen. Y Y Y p While the invention. has been particularly exemplified byV reference toits use in hydraulic presses, and illustrated as used in controlling a press employed in the molding of rubber valve stems for pneumatic tires, the invention is ofi` wider utility, as will now be apparent to those skilled in the art. While ,the` embodiment of the invention illustrated on the drawings has `been described in considerable detail, it is to be ex-,

pressly. understood that .the invention is not restricted thereto, as the same'is capable of receivvalve, and changes may also be made in details of construction, arrangement and proportion of parts, and certain features used without other features, Without departing from the spirit of this invention. Reference is therefore to be had to the claims appended hereto for a definition of the invention.

What is claimed is:

1. l'n a valve mechanism for controlling high and low pressure fluid in succession, a body having a high pressure valve means with an inlet adapted to be connected to a source of high pressure uid and an outletcommunicating with a chamber in said body, said chamber being adapted to communicate with al means to or from which said uid may flow, a low pressure exhaust valve means having its inlet in communication with said chamber and its outlet adapted to communicate with exhaust means, Aa common valve means having one of its passages communicating with said chamber and another passage adapted to communicate with a source of low pressure fluid whereby said, common valve means may supply low pressure fluid to said chamber or exhaust high pressure fluid from said chamber to said low pressure supply means, a common actuasti-,see

ator for all o f said valve means including a single rotatable member providedwith cam projections, one corresponding to each valve means, and means in the path of movement of each cam projectionV for operating its' corresponding valve means, the cam projections of the actuator being sowarranged that only one of either the high pressure, the exhaust or the common valve means may be openedat any time.` 1

2.1`In`a valve mechanism for controllingl high and low pressure fluid in succession, abody having. an high pressurevalvev means with an Vinlet adapted to be connected to a source of high pressure uid and an outlet communicating with a chamber in said body, said chamber being adapted to communicate with a means to 0r from which said iiuid may ow,'a low pressure exhaust valvemeans having its inletrin communication with said chamber and its -outlet adapted to communicate with 4exhaust means, a common valve means having one of its passages communieating with said chamber and another passage adapted to communicate with a source of low pressure fluid whereby said common valve means may supply low pressure fluid to said chamber or exhaust high pressure iiuid from said chamber to said low pressure supply means, a common actuator for all of said valve means including a single rotatable member provided with cam projections, one corresponding to each valve means, means in the path of movement of each cam projection for operating its corresponding valve means,y the cam projections of the actuator being so arranged that only one of either the high pressure, the exhaustV or the common valve means may be opened at any time, and pressure operated means for preventing movement of said actuator to a position for opening said high pressure'valve means until a predetermined pressure has been'establishedthrough operation of said common valve means for admitting low pressure fluid to said chamber.

3, In a valve mechanism for controlling high and low pressure fluid in succession, a body having a high pressure valve means with an inlet adapted `to be connected to a source of high pressure iluid and an outlet communicating with a chamber in said body, said chamber being adapted to communicate with a means to or from whichV said fluid may ilow, a low pressure exhaust valve means having its inlet in communication with said chamber and its outlet adapted to communicate with exhaust means, a common valve means having one of its passages communicating with said chamber and another passage adapted to communicate with a source of low pressure fluid whereby said common valve means'may supply low pressure fluid to said chamber or exhaust high pressure fluid from said chamber to said low pressure supply means, a common actuator for all of said valve `means including a single rotatable member provided with cani projections, one corresponding to each valve means, and means in the path of movement of each cam projection for operating its corresponding valve means, the cam projections of the actuator being so arranged that only one of either the high pressure, the exhaust or the common yvalve means may be opened at any time, at least one of said valve means for controlling exhaust including a pilot valve and meanswhereby said pilot valve is opened ahead of the exhaust valve means with which it is associated. y

4, In a Valve mechanism for controlling high asi-1,336

and low pressure duid in succession, a body having a high pressu-revalvewith an inlet adapted tol be connectedv to aA source of high pressure fluid and an outlet communicating with a chamber in said body, said chamber being adapted to communicate with a means to or from which said fluid may flow, a low pressure exhaust valve having its. inlet in communication Withf said chamber and its outlet adapted to communicate withA exhaust means, a high pressure exhaust valve and a low pressure admission valve controlling a com-mon passage which communicates at one end with said chamber and at its` other end with a source. of low. pressure iiuidA whereby said last named valves may supply low pressure tov said chamber or exhaust high pressure uid from said chamber to said low pressure supply means, a common actuator for said four valves including a sing-le rotatable disk provided; on its face with four cam projections, and means in the path of each ci said projections. and associated with one` of said valves for operating the same, said cam projection forsaid high pressure valve, saidcam projecting for said low pressure exhaust valve and the cam projections for fthe high pressure exhaust valve and low pressure admission valve being so. arranged that only the high pressure valve or he low,A pressure exhaust valve or the high pressure exhaust valve and low pressure admission valve. may be open at any time.

5. In a valve mechanism for controlling high and low. pressure fiuid in succession, a body having a high pressure valve with an inlet adapted to be connected to a source of high pressure fluid and an outlet communicating with a chamber in said body, said chamber beingadapted to communicate with a means to or from which said fluid may flow a low pressure exhaust valve having its` inlet. in communication with ,said chamber and its outlet adapted to communicate with exhaust means, a high pressure exhaust valve and a low pressure admission valve controlling a common passage which communicates at one end with said chamber and at its other end with a source of low pressure fluid whereby said last named valves may supply low pressure to said chamber or exhaust high pressure iiuid from said chamber to said low pressure supply means, a common actuator for said four valves including a single rotatable disk provided on its face with four cam projections, means in the path of each of said projections and associated with one of said valves for operating the same, said cam projection for said high pressure valve, said cam projection for said low pressure exhaust valve and the cam projections for the high pressure exhaust valve and low pressure admission valve being so arranged that only the high pressure valve or the low pressure exhaust valve or the high pressure exhaust valve and low` pressure admisison valve may be open atany time, and pressure operated means for preventing movement of said actuator to a position for opening said high pressure valve until a predetermined pressure has been established through operation of said valves controlling said common passage.

6. In a valve mechanism for controlling high and 10W pressure iiuid in succession, a body havins a high pressure valve with .an inlet adapted t0 be connected to a source ci .high pressure duid and an outlet communicating with a chamber in said body, said chamber being adapted to communicate with a means to or from which said til) fluid may dow, a low pressure exhaust valve having its inlet in communication with said chamber and its outlet adapted to communicate with exhaust means, a high pressure exhaust valve and a loivy pressure. admission valve` controlling a common passage which communicates at one end With .said chamber and at its other end with a, sourceof low pressure fluid whereby saidlast named valves may supply low pressure to said chamber or exhaust vhigh pressureY uid fromv said chamber to saidv low pressure supply means, a common actuator for said four valves including a single rotatable disk provided on its face with four cam projections, and. means in the path of each of said projections and associatedv with one of said valves for operating the same, said cam projection for said high pressure valve, said cam projection for said low pressure exhaust valve and the cam projections forI the high pressure exhaust valve and low pressure admission valve being so arranged that only theY high pressure valve or the low pressure` exhaust valve or the high` pressure exhaust valve and low pressure admission valve may be open vat any time, at least one of said valves for controlling exhaust including a pilot valve and means vwhereby said pilot valve is opened ahead oi the exhaust valve with which it is associated.

'7. In a valve mechanism for controlling high and low pressure fluid in succession, a body having a high pressure Valve with an inlet adapted to be connected to a source of high pressure fluid and an outlet communicating with a chamber in said body, said chamber being adapted to communicate with a means to or from which said iiuid may ilow, a loW pressure exhaust valve having its inlet in communication with said chamber and its outlet adapted to communicate with exhaust means, a high pressure exhaust valve and a low pressure admission valve forming a valve means controlling a common passage which communicates at one end with said chamber and at its other end With a source of low pressure iiuid whereby said last named Valve means may supply low pressure to said chamber or exhaust high pressure fluid from said chamber to said low pressure supply means, and a common actuator constructed and arranged to operate. said valve means, said high pressure valve andl said low pressure exhaust valve in DTQPEIT Sequence- 8.. In e valve mechanism ier controlling high and low pressure fluid in succession, a body having a high pressure valve with an inlet adapted to be connected to a source of hichpressure fluid andan outlet communicating with a chamber in said body, said chamber beine adapted to ccmmunicate with a means to or from which said iiuid may flow, a low pressure exhaust valve having its inlet in communication with said chamber and its outlet adapted to communicate with exhaust means, a high pressure exhaust valve and a low pressure admission valve forming a valve means controlling a common passage which communicates at one end with said chamber and at its other end with a source ci `low pressure huid whereby said last named valve means may supply low pressure to said-chamber or exhaust high pressureuid from said chamber to said low pressure supply means, a commonactuator constructed and arranged to operate said valve means, said high pressure valve and said low pressure exhaust valve in proper sequence, said common actuator including a rotatable disk, a'

member for rotating said disk and means in the path of said member for stopping the rotation of said disk in the positions `of said common actuator corresponding respectively to the full opening of the high pressure valve, full opening of the low `pressure admission valve and full opening of t' the low pressure exhaust valve.

9. In a valve mechanism for controlling high and low pressure fluid in succession, a body havits other end with a source of low pressure fluid whereby said last named valve means may supply low. pressure to said chamber or exhaust high pressure huid from said chamber to4 said lowV pressure supply means, a common actuator constructed and arranged to operate said valve means, said high pressure valve and said low pressure exhaust valve in proper sequence, saidk y common actuator including a rotatable disk pro-` vided on its face with cam projections, one corresponding to each valve, and a plunger aligned with each valve and adapted to be actuated by the corresponding cam projection to move said plunger and lift the corresponding valve from its seat.

10. In a valve mechanism for controlling high and low pressure iiuid in succession, a body having a high pressure valve with an inlet adapted to be connected to a source of high pressure fluid and an outlet communicating with a chamber in said body, said chamber being adapted to communicate with a means to or from which said fluid may flow, a low pressure Yexhaust valve having its inlet in communication with said chamber and its outlet adapted to communicate with exhaust means, a high pressure exhaust valve and a low pressure admission valve forming a valve means controlling a common passage which' communicates at one end with said chamber and at its other end with a source of low pressure iiuid whereby said last named valve means may supply low pressure to said chamber or exhaust high pressure fluid from said chamber to said low pressure supply means, and a common actuator constructed and arranged to operate said valve means, said high pressure valve and said` 10W pressure exhaust valve in proper sequence, at least one of said exhaust valves being provided with apilot valve for releasing the pressure thereon preliminarily to the opening of said exhaust valve.

11. In a valve mechanism for controlling high and low pressure iiuid in succession, a body having a high pressure valve with an inlet adapted to be connected to a source of high pressure iiuid and an outlet communicating with a cl'i'amber in said body, said chamber being adapted to communicate with a means to or from which said iiuid may flow, a low pressure exhaust valve having its inlet in communication with said chamber and its outlet adapted to communicate with exhaust means, a high pressure exhaust valve and a low pressure admission valve forming a valve means controlling a common passage whichv com- `municates at one end with said chamber and at ing a, high pressure valve with an inlet adapted its other end with' a source of low pressure iluid whereby said last named valve means may supply low pressure to said chamber or exhaust high pressure fluid from said chamber to said low pressure supply means, and a common actuator constructed and arranged to operate said valve means, saidV high pressure valve and said low pressure exhaust valve in proper seziuence, at least one of said exhaust valves being provided With a port therethrough and a pilot valve member cooperating with said port and having an extension beyond said exhaust valve, said extension adapted io be operated by said actuator to open said pilot valve before said exhaust valve is opened.

12. In a valve mechanism for controlling high and low pressure uid in succession, a body having a high pressure valve with an inlet adapted to be connected to a source of high pressure4 fluid and an outlet communicating with' a chamber in said body, said chamber being adapted to communicate with a means to or from which said fluid may flow, a low pressure exhaust valve having its inlet in communication with said chamber and its outlet adapted to communicate with exhaust means, a high pressure exhaust valve and a low pressure admission valve forming a valve means controlling a common passage which communicates at one end with said chamber and at its other end with a source of low pressure fluid whereby said last named valve means may supply low pressure to said chamber or exhaust high pressure uid from said chamber to said low. pressure supply means, a common actuator constructed and arranged to operate said valve Y means, said high pressure valve and said Alovv pressure exhaust valve in proper sequence, said common actuator including a rotatable disk provided With four cam projections and plungers aligned with the respective valves and adapted to cooperate with said cam projections to o pen said valves, and means to stop said disk after said high pressure exhaust valve and said low pres.- sure admission valve have been opened and to prevent further rotation thereof toward that position wherein the high pressure valve is opened until a predetermined pressure exists in said outlet.

13. In a valve mechanism for controlling high and low pressure fluid in succession, a body having a high pressure valve with an inlet adapted to be connected to a source of high pressure fluid and an outlet communicating with a chamber in said body, said chamber being adapted to Communicate with a means to or from which said fluid may iiow, a low pressure exhaust valve having its inlet in communication with said chamber and its outlet adapted to communicate with exhaust means, a high pressure exhaust valve and a low pressure admission valve forming a, valve means controlling a common passage which communicates at one end with said chamber and at its other end with a source of low pressure fluid whereby said last named valve means may supply 10W pressure to said chamber or exhaust high pressure fluid from said chamber to said low pressure supply means, a common actuator constructed and arranged to operate said valve means, said high pressure valve and said low pressure exhaust valve in proper sequence, said common actuator including a rotatable disk provided with four cam projections and plungers aligned with the respective valves and adapted to cooperate with said cam projections to open said valves, and means to' stop said disk after said highl pressure exhaust valve vand said low pressure admission valve have been-opened and to zpr-event further rotation thereof-'towar.d that position wherein the'highpressure. valvelis opened until a .predeterminedpressure .exists .in said outlet, lsaid last named means including a pivotallymounted ilever provided with a stop face and pressure operated means communicating with said chamber and cooperating with .said lever to withdraw said stopace whenza predetermined pressure exists in said chamber.

14. In .a valve mechanism for controlling high and low Vpressure iluid in succession, a `body having .a high pressure valve with an inlet. adapted to be connected to a sourceof high pressure .fluid andan outlet .communicating with a chamberin said body, vsaid chamber being adapted to communicate with a means to` vor from which said uid may flow, a `low pressure exhaust valve having its inlet in communication :with said chamber.. and its outlet adapted to communicate with' exhaust means, a high pressureY exhaust valve and a low pressure admission Avalve forming Aa valve means controlling a common passage which communicates at `one end with` said chamber .and at its other .end with .a source Iof low pressure liuid whereby said- Alastznamed` valve means maysupply low .pressure to said chamber or exhaust high pressure fluid from said chamber to said low pressure .supply means, vand a common actuator constructed and arranged -to operate said valve means, said high pressure valve and said low pressure exhaust valve in proper sequence, said `common .actuator including a rotatable .disk providedvwith four cam projections and plungers associated with' the respective cam projections and aligned withthe respective valve 'members .to openthe same, .eachof said exhaust valves including a pilotvalve which is also opened Aby the plunger .associated with the corresponding exhaust valve before the Said exhaust valve is opened. f

15. In a valve mechanism for controlling high and low pressure fluid in succession, a body having a high pressure valve with an inlet adapted to be connected to asource .ofihigh pressure yiiuid and an outletcommunicating with a chamber in said body, saidchamber being adapted to communicate with a means .to or from which said fluid may ow, a W pressure exhaust valve having its inlet in communication with said chamber and its outlet adapted to vcommunicate with exhaust means, a high :pressure exhaust valve and a low pressure admission valve forming a valve means controlling a common passage which communicates at vone end with said .chamber and .at its other end with a source-of low .pressure uid whereby said last named valve means maysupply low pressure to said chamber Vorexhaust v,high pressure fluid from said chamber .to said. low pressure supply means, and a common actuator constructed and arranged to operate said valve means, said high pressure valve and said low pressure exhaust valve in proper sequence, said common actuator including a rotatable disk provided With four cam projections, plungers associated with the respective cam projections and aligned with the respective valve members to open the same, each of said exhaust valves being provided with a port therethrough and a pilot valve member cooperating with said port and having a pin projecting beyond the associated exhaust valve member into the path of movement of the associated plunger whereby said plunger opens said pilot valve through engagement with said Din before engagin'g the exhaust valve membergto'openthe same. z 1

316; Ina valve mechanismior controlling the flow of high .and low `pressure uuid in succession, a'body having a highpressure valvewith an inlet adapted to .be connectedto :a source :of .high pressure iiuid and an outlet communicating with a chamber in said body, operating means for said high -pressure valve, said .chamberzbeing adapted to communicate with ,a means to or from which said fluid may flow, a low pressure exhaust valve having y'its Vinlet in 4communication with vsaid chamber `andgits outlet adapted to communicate with exhaust means,y .operating means for said low pressure exhaust' valve' and r:means for exhausting 'high' pressure fluid from said chamber toa low pressure Vsupply means and -for admitting low pressure fluid from said low pressure supply means vto said chamber including a single passage communicating with said chamber and said low -pressure supply means, a pair of :main valve Amembers cooperating lwith valve. seats vin said passage, a-pilot valve associated `with one of said main valve members, and common means for opening both .of said'rmain valve members when low pressure uid is .to be admitted to said chamber and for first .opening :said pilot valve and cracking x.the .other main valve member and thereafter opening `sbotl-i'of said .main valve members wide when high pressure Huid is Ato be exhausted .from said chamber.

17. In a valve mechanism -for controlling the now of highand low pressure liuid in succession, a body having a high pressure valve with an inlet adapted to be connected to a source of high pressure uid and :an .outlet ycommunicating with a chamber 1in lsaid body, operating means yfor said high pressure valve, said ,chamber being Aadapted to communicate lwith' .a means to .or from which said iluid may ow., a low pressure exhaust valve having 'its .inlet in communication with said chamber and lits outlet adapted .to communicate with exhaust means, .operating means for said low pressure exhaust'valve, and means `for exhausting 'high pressure liuid from said chamber to' a low pressure .supplv'means' and for admitting low ypressure iuid from said low pressure supply means to said chamber including .a sing-1e passage communicating with 'said :chamber and said low pressure supply means, a pair .of main valve mem-bers cooperating with Ivalve seats in said passage, `a pilot valve associated with one of vsaid main valve members, and .common vmeans for opening both' of said 'main valve members when low pressure fluidis tobe admitted to said chamber and .for rst .opening Asaid pilot valve and cracking the otherrmain valve member `andtherea-fter opening Vboth .of said A.main valve members wide when high Dressurefluid is to be ,exhausted from said chamber, fsaid last named .means .in-

cludi-ng a single rotatable .disk :ha-vingjcam pro.

jections and means cooperating ytherewith .for operating said valve members.

18. In a valve mechanism for controlling the flow of high and low pressure fluid in succession, a body having a high pressure valve with an inlet adapted to be connected to a source of high pressure uid and an outlet communicating with a chamber in said body, said chamber being adapted to communicate with a means to or l I from which said fluid may flow, a low pressure exhaust valve having its inlet in communication with said chamber and its outlet adapted to communicate With exhaust means, and means for exhausting high pressure fluid from said cham ber to a low pressure supply means and for admitting low pressure fluid from said-low pressure supply means to'said chamber including asingle passage communicating with-said chamber and said loW pressure supply means, a pair of main valve members cooperating ywith valve seats in said passage, a pilot valve associated with one of said main valve members, and common means for opening both of said main valve members when low pressure uid is to be admitted to said chamber and for first opening said pilot valve and cracking the oth'er main valve member and thereafter opening both of said main valve members Wide when high pressure fluid is to be exhausted from said chamber, said last named means including a single actuator provided with cam projections and plungers associated with` said cam projections and said valve members for operating the latter from said cam projections, said actuator also including other cam projections and plungers associated therewith and with said high' pressure valve and said low pressure exhaust valve for operating the latter only when the rst named valve members are closed, said last named cams being so arranged that only said high pressure valve or said low pressure exhaust valve is open at any one time depending upon the direction of movement of said actuator,

19. In a valve mechanism for controlling the flow of high and low pressure fluid in succession, a body having a high' pressure valve with an inlet adapted to be connected to' a source of high pressure fluid and an outlet communicating with a chamber in said body, said chamber being adapted to communicate with a means to or from which said fluid may flow, a low pressure exhaust valve having its inlet in communication with said chamber and its outlet adapted to communicate with exhaust means, and means for exh'austing high pressure fluid from said chamber to a low pressure supply means and for admitting low pressure fluid from said low pressure supply means to said chamber including a single passage communicating with said chamber and said low pressure supply means, a pair of main. valve members cooperating with valve seats in said passage, a pilot valve associated with one of said main valve members, and common means for opening both of said main valve members when loW pressure iiuid is to be admitted to' said chamber and for first opening said pilot valve and cracking the other main valve member and thereafter opening both' of said main valve members Wide when high pressure iiuid is to be exhausted from said chamber, said last named means including a single actuator provided with cam projections and plungers associated with said cam projections and said valve members for operating the latter from said cam projections, said actuator also including other cam projections and plungers associated therewith and with said high pressure valve and said low pressure exhaust valve for operating th'e latter only when the first named valve members are closed, said last named cams being so arranged that only said high pressure valve or said low pressure exhaust valve is open-at any one time depending upon the direction ofy movement of saidactuator, and means associated with said actuator for preventing movement thereof to the position for opening said high pressure. valve until said first named valve members have been opened to establish a predetermined pressure .in said chamber.

20. In a valve mechanism for controlling th'e flow of high and low pressure uid in succession, a body having a high pressure valve with an inlet adapted to be connected to a source of high pressure uid and an outlet communicating with a chamber in said body, said chamber being adapted to communicate with a means to or from which said fluid may flow, a low pressure exhaust valve h'aving its inlet in communication with said chamber and its outlet adapted to communicate with exhaust means, and means for exhausting high pressure fluid from said chamber to `a low pressure supply means and for admitting low pressure `uid from said low pressure supply means to said chamber including a single passage communicating with said chamber and said low pressure supply means, a pair of main valve members cooperating with valve seats in said passage, a pilot valve associated with one of said,

main valve members, common means for opening both of said main valve members when low pressure fluid is to be admitted to said chamber and for rst opening said pivot valve and cracking the other main valve member and thereafter opening both of said main valve members wide when high pressure iiuid is to be exhausted from said chamber, said last named means including a single actuator provided with cam projections and plungers associated with said cam projections and said valve members for operating the latter from said cam projections, said actuator also including other cam projections and plungers associated therewith and with said high pressure valve and said low pressure exhaust valve` for operating the latter only when the iirst named valve members are closed, said last named cams being so arranged'that only said high pressure valve or said low pressure exhaust valve is open at any one time depending upon the direction of movement of said actuator, and means associated with said actuator for preventing movement thereof to the position for opening said high pressure valve until said iirst named valve members have been opened to establish a predetermined pressure in said chamber, and said low pressure exhaust valve also being provided with a pilot valve which is opened by its associated plunger before said exhaust valve is opened by said plunger. f

HENRY Z. GORA. 

